The internet teems with self-help sites that promise to help people improve their health. But which of these outlets have been evaluated through gold-standard studies and have evidence to support their claims?

A new paper compiles only the best of the best: a list of more than 40 sites backed by evidence from randomized controlled trials.

Compiled by a team at the University of Michigan Medical School, the list includes sites that offer people help with reducing their use of alcohol, tobacco and marijuana; managing mental health issues; and improving diet and physical activity. Other topics include insomnia, chronic pain, cardiovascular risk and childhood health issues.